I wonder if he was misquoted in this 2005 Esquire interview drudged up by Matthew Reichbach at The New Mexico Independent:
(Question)You understand how it feels to shoot someone as much as a person who has actually committed a murder?
(Answer): I understand it more. It’s an actor’s job. A guy who’s lived through the horror of Vietnam has not spent his life preparing his mind for it. He’s some punk. Most guys were borderline criminal or poor, and that’s why they got sent to Vietnam. It was all the poor, wretched kids who got beat up by their dads, guys who didn’t get on the football team, couldn’t finagle a scholarship.
They didn’t have the emotional equipment to handle that experience. But this is what an actor trains to do. I can more effectively represent that kid in Vietnam than a guy who was there.
Reichbach quotes a military families blog that calls Kilmer the "brass-balled moron of the year.”
UPDATE: The entire Esquire interview, by Chuck Klosterman, is HERE.